1. Field of the Invention
The subject invention relates to a pin field inserted in a printed circuit board, with back-to-back headers positioned on opposite sides of the printed circuit board.
2. Description of the Prior Art
It is well known to form a pin field in printed circuit boards. These pins would be electrically connected to circuit traces in a printed circuit board, by way of press fit, such as for example by way of compliant pin portions within the printed circuit board through hole. Extending in opposite directions from the compliant pins, are pin portions, profiled for mating with complementary terminals in a complementary connector. Housings are positioned over the pins on opposite sides of the printed circuit boards to form a completed connector assembly. A difficulty which has arisen, is the method of retaining the housings to the pin field.
The printed circuit boards of the subject pin fields may have through holes having a diameter as small as 0.55 mm in diameter. Thus, the pin has on one side of the compliant pin portion, an enlarged barb, which is larger than the nominal width of the pin, which is profiled for interference fit within the corresponding housing. However, as the pin must be inserted through the printed circuit board through hole, the side of the pin opposite the entry side of the printed circuit board cannot contain a retaining board, as it would not fit through the printed circuit board. Therefore, on one side of the printed circuit board, the pin is of a constant width, sometimes as narrow as 0.50 mm. The housings which enclose these pins generally have passageways which are interference fit with the pins.
One of the drawbacks to this approach is that, as the housings are inserted over the pin field, the housings interfere with the pin field, and leave some of the plastic on the pins themselves which could lead to an unstable contact, as the plastic is directly on the contact surfaces. Thus, as the mating contact receptacle could have plastic particles between the contact surfaces and the pin itself, an ineffective contact could be made. Secondly, as many housings are made from glass filled housings, the glass particles in the housing could actually skive through the gold plating on the contacts, again leading to an ineffective contact system.